package com.atguigu;

import java.util.concurrent.CountDownLatch;

/**
 * @ClassName CountDownLatchDemo
 * @Author yy
 * @create 2022/9/7 20:33
 */

//CountDownLatch减少计数

/*
 * CountDownLatch主要有两个方法，当一个或多个线程调用await方法时，这些线程会阻塞。
 * 其它线程调用countDown方法会将计数器减1(调用countDown方法的线程不会阻塞)，
 * 当计数器的值变为0时，因await方法阻塞的线程会被唤醒，继续执行。
 */

public class CountDownLatchDemo {
    public static void main(String[] args) throws InterruptedException {
        CountDownLatch countDownLatch = new CountDownLatch(6);

        for (int i = 1; i <= 6; i++) {
            new Thread(()->{
                System.out.println(Thread.currentThread().getName()+"\t"+"离开自习室");
                countDownLatch.countDown();
            },String.valueOf(i)).start();
        }

        countDownLatch.await();

        System.out.println(Thread.currentThread().getName()+"\t"+"班长关门后走人");
    }
}
